Rewelded cartridge and method of manufacture

ABSTRACT

A reassembled laser toner cartridge and method of manufacture in which the hopper section and roller section of a previously depleted toner cartridge are rewelded together by ultrasonic welding along the length sections after an ancillary energy director strip has been positioned between the sections where the roller section interfaces with the hopper section to provide a laser toner cartridge that has the same or nearly the same specifications as the original equipment manufactured cartridges.

TECHNICAL FIELD OF INVENTION

The present invention relates to improvements in the field of lasertoner cartridge remanufacturing in which a previously spent tonercartridge is disassembled, and then reassembled and resealed byinserting ancillary energy director material between a hopper sectionand a roller section and then ultrasonically welding the two sectionstogether. This process results in improved product performance,increased production efficiency, and decreased production cost, due tothe process bringing the cartridge back to its original specification orclose to that specification.

BACKGROUND ART

Laser toner cartridges are manufactured to a high degree of precisionnecessary for proper operation and good printed image quality. Ofimportance to the proper operation of a laser toner cartridge is themaintenance of alignment and orientation of its various components.Original equipment manufactured (OEM) cartridges achieve the rigiditynecessary to maintain the alignment and orientation of components, insubstantial part by ultrasonically welding sections of the toner, orprocess, cartridge together.

The process of repairing or remanufacturing such a cartridge requiresthat the cartridge be disassembled and that the hopper section of thecartridge, which holds the toner, be separated from the magnetic rollersection, which contains the magnetic or developer roller and othercomponents. When the hopper and roller sections have been separated andare subsequently joined back to each other, or to corresponding sectionsof other previously depleted cartridges, precise alignment andorientation of performance critical components are necessary during theremanufacturing and reassembly process, particularly between the rollerand the hopper sections.

A conventional approach to this problem is careful manual alignment andfitting of the two sections together, with or without the aid of apositioning jig, and then manual securing of the sections together witha number of metal clips. Alternatively, the sections maybe fastenedtogether with adhesive or glue. These techniques, while generallyeffective, suffer from a number of deficiencies or drawbacks.

The most common drawback is that the dimensional height of the rollerand/or hopper section has been changed when compared to the cartridge'soriginal specifications. Another drawback is that both metal clips andadhesives are consumables, and their use increases production costs andfinal product cost of manufacture. Another significant drawback is thatmanual reassembly is quite labor intensive, as well subject to humanerror and variations in quality. In reassembly with adhesive or glue, aperiod of a few, to several minutes is required for bonding to takeplace and during which time precise alignment must be maintained. Anadditional drawback to the use of metal clips to reassemble thecartridge sections is that the rigidity imparted by the originalultrasonic weld is difficult to achieve, and over the working life of aconventionally reassembled cartridge the clips may loosen or becomedisengaged entirely. In such an event, as a result of a loss of properalignment of the hopper seal and/or roller section, excessive toner mayaccumulate on the roller with the result being an excessive amount oftoner on the roller. This excess toner is then transferred to thephotoconductive printing drum and then to the printer paper, therebyresulting in unsatisfactory finished product quality. Further,disengagement of a metal clip may permit toner to leak from thecartridge. In many printing devices, such as printers, facsimilemachines or copiers, the path of the paper through the printing devicepasses nearby to the edge of the toner cartridge where the metal clipshave been installed. Paper jams can occur if a loose metal clip projectsinto the paper path.

Original equipment laser toner cartridge sections are typically joinedtogether by an ultrasonic welding process. A primary impediment to theuse of ultrasonic welding in the rejoining of previously used or spentcartridge sections has been the absence of an energy director element,usually due to the destruction of the energy director material when thespent cartridge is disassembled by sawing the cartridge at the planewhere the original roller section and hopper section were joined by theinitial ultrasonic weld.

As is understood in this field, an energy director element is a materialthat is typically in the form of a ridge or bump, extending slightlyabove the surface of the surrounding area and contacting the surface(s)to be welded. It is typically, originally molded on the surface ofeither the roller section or the hopper section for original equipmentcartridges, and is made typically of an organopolymeric material such asABS or polystyrene. The energy director is of the same material as thehopper and roller sections of the cartridge and is formed in the mold inwhich the plastic component is created. The energy director material orelement is in direct contact with the surface to be ultrasonicallywelded. During the ultrasonic welding process, it is the energy directorelement that is first melted or fused as a result of the frictioncreated between the two surfaces to be welded by the ultrasonicvibrations. It is the melting or fusing together of the surfaces to bebonded, at the location of the energy director element that, uponcooling, solidifies and seals the hopper section to the roller section.The energy director element is often largely or entirely consumed in theoriginal manufacture of a new toner cartridge. Hence, upon separation ofthe hopper and roller sections at the location of the originalultrasonic weld in preparation for a remanufacturing process,insufficient residual energy director might remain to accomplishrewelding to join or reseal a previously spent hopper to a previouslyspent roller section. The present invention is directed to solving theseproblems by providing a reassembled toner cartridge and method ofmanufacture in which previously spent hopper sections and previouslyspent roller sections may be ultrasonically welded to previously spentor to new complementary sections with the use of ancillary energydirector material placed between the two sections to be ultrasonicallywelded together.

DISCLOSURE OF INVENTION

The present invention improves the appearance and operationalperformance of laser toner cartridges, which have been recycled orremanufactured from components of depleted toner cartridges, andprovides a method whereby this may be accomplished.

It is a primary object of the present invention to provide an improvedmethod of rejoining subassemblies of previously depleted tonercartridges without the use of mechanical fasteners, such as adhesives,screws, clips, rivets or the like.

A further object of the present invention is to provide an improvedmethod of rejoining subassemblies of previously depleted recycled tonercartridges, which permits the toner cartridge to be separated again atthe location of the rejoining and that employs ultrasonic welding.

It is yet another object of the present invention to provide an improvedmethod of rejoining subassemblies of toner cartridges that reduces humanerror in the rejoining process.

It is yet another object of the present invention to provide an improvedmethod of rejoining subassemblies of toner cartridges that employsultrasonic welding with use of a specially fabricated ancillary energydirector strip.

It is yet another object of the present invention to provide an improvedmethod of rejoining subassemblies of toner cartridges that achieves andmaintains, over the entire working life of a recycled or remanufacturedtoner cartridge, the proper alignment and position of the hopper andpull-seal and relative to the roller.

It is yet another object of the present invention to provide an improvedmethod of rejoining subassemblies of recycled or remanufactured tonercartridge that is uniformly reproducible and reliable.

It is another object of the present invention to provide an improvedmethod of rejoining subassemblies of recycled or remanufactured tonercartridges that is faster than conventional manual methods.

It is a further object of the present invention to provide a recycled orremanufactured toner cartridge that is resealed by ultrasonic welding.

It is a further object of the present invention to provide a recycled orremanufactured toner cartridge that is resealed by ultrasonic weldingwith or without the use of a specially fabricated ancillary energydirector element.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects and advantages of the invention will become apparent fromthe forgoing detailed description taken in connection with theaccompanying drawings.

FIG. 1 is a perspective view of a prior art remanufactured tonercartridge.

FIG. 2 is a perspective view of an embodiment of a remanufactured tonercartridge of the present invention.

FIG. 3 is partially disassembled perspective view of the FIG. 2embodiment.

FIG. 4 is a perspective view of a typical apparatus used in theultrasonic welding process for manufacture of the FIG. 2 embodiment.

FIG. 5 is an end view of the FIG. 4 ultrasonic welder horn prior to thewelding step of the process of manufacture of the FIG. 2 embodiment.

FIG. 6 is an end view of the FIG. 4 ultrasonic welder horn immediatelyafter the welding step of the process of manufacture of the FIG. 2embodiment.

FIG. 7 is a schematic, cross-sectional view of the FIG. 4 ultrasonicwelder horn and cartridge sections immediately prior to energizing theultrasonic welder.

FIG. 8 is a schematic view showing the ultrasonic welding horn duringthe welding process.

BEST MODE FOR CARRYING OUT THE INVENTION

To illustrate and further describe preferred embodiments reference willbe made to FIGS. 1-8.

With reference to FIG. 1, conventional repaired or remanufacturedplastic laser toner cartridge (20) includes toner hopper section (22)and magnetic or developer roller section (24) fastened together byconventional clips (26). Clips (26) function to hold together the tonerhopper section (22) and the roller section (24). During its repairprocess typically the cartridge is split by sawing it into two sections,i.e., the hopper section (22) and the roller section (24), which arethen typically held together by clips (26).

With reference to FIG. 2, a first embodiment of the inventive cartridge(28) is shown. The laser toner cartridge (28) includes toner hoppersection (30) and magnetic or developer roller section (32) fastenedtogether by a preferred ultrasonic welding method of manufacture thatincludes use of ancillary energy director material. Other embodimentsinclude cartridges of different shapes and of different materials ofconstruction.

FIG. 3 is a partially disassembled perspective assembly view of the FIG.2 cartridge components shown prior to ultrasonic welding. Two ancillaryenergy director strips (34, 34) are shown positioned between hoppersection (30) and roller section (32). A conventional toner hopper sealpull strip (36) and a conventional toner hopper port perimeter seal (38)are also positioned between the hopper and roller sections. Otherconventional components and subassemblies and components are not shown,for clarity in describing features of the present invention. The strip(36) functions to seal the hopper during shipping and storage to preventinadvertent toner leakage. The strip (36) is removed prior to operation.The perimeter seal (38) functions to seal the sections and prevent tonerleakage inside of the printer during operation. The strip (36) isconventional, is commercially available under the designation Mylar andhas an adhesive backing (40) at its outer periphery, the boundary ofwhich is illustrated schematically at dashed lines (42) shown in FIG. 3.Typically seal (38) is made of a conventional foam material such aspolyurethane closed cell or open cell foam.

It has been discovered that under certain conditions ancillary energydirector strips (34, 34) are advantageously employed to repair orremanufacture cartridges. For example, when a cartridge is split bysawing, material from the original cartridge necessarily is lost. Whencartridges have been disassembled by use of a circular saw cuttingblade, typically a flat surface remains on the hopper section and theroller section at the cutting plane. The material at these planes iswhere the ancillary energy director fuses and is welded to the hopperand roller sections.

In order to return the repaired or remanufactured cartridge to originalequipment specifications or as close to possible to original equipmentspecifications, it is preferred that appropriate energy directormaterial is added during the repair process. It has been found that byusing material that is the same as the material of the originalcartridge, and placing this material between the hopper and rollersections prior to ultrasonic welding, this material functions as aenergy director during the welding process. It also functions to replacematerial that has been lost by the disassembly process. Anotheradvantageous feature of a remanufacturing process that uses an ancillaryenergy director is that if a significant amount of the original hoppersection or roller section material is lost due to disassembly, theancillary energy director material or strip can function as a shim tocontribute to making a remanufactured cartridge with dimensions that arewithin the specifications for the original cartridge. The ancillaryenergy director material is commercially available from ShoonIndustries, and in sizes and thicknesses made to order for theparticular application at hand. It is most preferred that when usingancillary energy material, all of the original energy director materialfrom the depleted cartridge section(s) to be remanufactured be removed.It is most preferred that the surfaces to be joined by the presentinventive method be smooth so that the ancillary energy directormaterial may be placed flat on one of the surfaces. It has been foundthat when the surfaces are not flat, an increased probability of anincomplete weld results, with a consequential potential for leakage oftoner out of the remanufactured cartridge.

As will be appreciated, the material used, shapes and dimensions of thestrips (34, 34) can be varied according to the material of the originalcartridge and the degree and location of the original cartridge materiallost during the disassembly process. Typically the cartridges, as wellas the ancillary energy director material are made from ABS plastic orhigh impact styrene. The height of an ancillary energy director isprimarily dictated by the amount of material lost when sawing orotherwise separating the roller housing from the hopper section. Varyingthe height or thickness of the strip in this way enables the repaired orremanufactured cartridge to be brought back to the OEM specification.Thus, the resulting repaired toner cartridge provides for a quality ofprinting as close as possible to that of an OEM cartridge. The preferredheight and width for each strip (34) is about 0.030 inch. The strips(34, 34) shown in FIG. 3 are preferably linear with a squarecross-section, but other shapes may be used.

As shown in FIG. 3, the strips (34, 34) preferably lie along only thelongitudinal axis of the hopper, on each side, and thus function notonly to fasten the hopper section to the roller section, but also toseal the cartridge at these locations. The foam seal (38) functions toseal either end of the cartridge during use. Also with reference to FIG.3, the hopper section (30) includes a toner port seal surface (44),shown here in a recess in the hopper section, and forming the topentrance to cavity (46) in which the toner is placed. The toner portseal surface (44) at the top of the formed port cavity is adapted toaccept and mate with the surface of adhesive backing (40) of the strip(36) and perimeter seal (38). Also, the toner hopper section (30)includes a toner fill port (48), which after filling the cavity (46)with toner is closed by hopper cap (50).

FIG. 4 illustrates a perspective view of a preferred ultrasonic weldingdevice (52) and a holding fixture (54) shown holding the FIG. 2cartridge 28 in a preferred position to be welded. During theremanufacturing process ultrasonic welding horn (56) drops down ontocartridge flanges (58, 58) of the roller section (32). Once the weldingdevice is activated it melts the ancillary energy director strips tofuse or weld the hopper section to the roller section and thereby form arepaired or remanufactured cartridge.

During a typical remanufacturing process a cartridge is refilled withtoner to make a prepared hopper, and the pull strip is then attached tothe surface of the toner hopper port. Next the perimeter hopper portseal is put into place using the adhesive backing. Once the full hopperand its related seals are in place, then the roller housing is placedinto position to be ultrasonically welded. Once the cartridge is placedinto the holding fixture (54), it is clamped into position by apneumatically operated holding bar (60) which is adapted to reciprocatealong static slider block (62). In this position the laser tonercartridge is ready to be ultrasonically welded. Next welding horn (56)is dropped down onto the flanges (58, 58) of the roller section and thenultrasonically welded upon activation of the device. Typically theactual welding takes place in a few seconds, depending on the type andthickness of the energy director material. After the toner cartridgehopper and roller sections have been welded together, the holdingfixture is released, the cartridge is removed and another cartridge isplaced into position to be welded.

FIG. 5 is an end view of the ultrasonic horn (56) moving toward theflanges (58, 58) in the direction shown by arrow (64) before makingcontact. FIG. 6 is an end, snapshot view of the horn (56) moving awayfrom the flanges (58, 58) in the direction shown by arrow (66) afterwelding the hopper and roller sections together. Arrows (68, 68) showthe location of the ancillary energy director material (34, 34) that hasbeen fused to and welds the hopper and roller sections together.

FIG. 7 is a schematic, cross sectional view of the cartridge reweldingprocess at the moment of energizing the ultrasonic welding device. Theancillary energy director strips (34, 34) are shown in position betweenthe upper surface of the hopper section (30) and the lower surface ofthe roller section (32). The horns (56) are shown just prior to pressingdown on the assembly. FIG. 8 is a front schematic view of the reweldingprocess while the ultrasonic welder is energized. Wave lines (70)represent the sound waves being transmitted from the device to theancillary energy director material (34) in the direction shown by arrows(72) at a frequency and intensity sufficient to cause the material (34)to fuse and weld the hopper section to the roller section. The preferredlocation for ultrasonic welding is on the same flanges that the originalequipment cartridge was welded.

Preferred steps and procedures of the inventive method of remanufactureof the reassembled laser toner cartridge begin with visual inspection ofthe toner cartridge for damage and whether it is suitable to beremanufactured. The cartridge is then partially disassembled to removeexternal components such as the waste hopper, gear housing end plates,rollers and the toner hopper cap. Next, any residual toner is removedand the cartridge is cleaned.

The roller section is then separated from the hopper section along theplane or flanges of the ultrasonic weld that joins the two sectionstogether. Components are inspected for cleanliness and integrity andmaybe re-used, or discarded, or re-cleaned as appropriate. A tonerhopper seal pull strip is installed. Next the toner hopper tank isfilled with the appropriate toner for a particular application. Thetoner hopper fill cap is then typically installed, after which the tonerhopper tank is tested for leaks.

The magnetic or developer roller section is then mated with therecharged toner hopper section and the loose assembly is placed into aclamp jig which has been constructed to properly align and configure theparticular type or model of cartridge being processed. The clamp jig isoperated to impose the preferred alignment and configuration on thecartridge assembly. While the cartridge is clamped in the jig, theultrasonic welding horn is lowered and energized to weld (or fuse) theroller section to the toner hopper section. This welding processrequires approximately one second. The pressure on the welded flanges ismaintained by the welding apparatus, for approximately 10 seconds, untilthe bond has cured, after which the resealed and ultrasonically weldedcartridge is moved from the welding jig.

Following resealing of the recharged laser toner cartridge, othercomponents, such as the magnetic or developer roller, photoconductivedrum, new or reconditioned and blades are installed in the rollersection. Finally, the waste hopper is installed and the finishedreassembled toner cartridge is subjected to a “post-test” qualitycontrol testing, after which it is packaged for shipment.

While the present invention has been described in connection with whatare presently considered to be the most practical and referredembodiments, it is to be understood that the invention is not to belimited to the disclosed embodiments, but to the contrary, is intendedto cover various modifications and equivalent arrangements included withthe spirit of the invention, which are set forth in the appended claims,and which scope is to be accorded the broadest interpretation as toencompass all such modifications and equivalent structures.

1-2. (canceled)
 3. A reassembled toner cartridge comprising: a. apreviously depleted toner hopper section; b. a roller section; and c.ancillary energy director material ultrasonically fused to the hoppersection and ultrasonically fused to the roller section to form thereassembled cartridge.